Should I Worry About Ukulele Humidity? | GOT A UKULELE - Learn Ukulele, beginners tips and reviews

10 May 2015

Should I Worry About Ukulele Humidity?

OK, something that kind of gets my goat this one, and in danger of descending into a famous Got A Ukulele rant... Do you need to worry about ukulele humidity?

Why only a  potential rant Baz? Well, I realise that we live on a BIG planet and for many people, humidity is indeed a BIG problem with solid wood instruments. I suppose what started to get the hackles up with me was when I see people in the UK ( a temperate climate) worrying about humidity and, worse, still, spending money on gadgets to solve a problem that some bright spark convinced them was real. Not only can in many cases such gadgets be unnecessary, but they can cause as much damage the other way.

OK, back to basics. Humidity, or to be more precise 'relative humidity' is a measure of how much moisture there is in the air. The term 'relative' is an important one as humidity is measured as a percentage and it is not a measure of liquidity. A high humidity is something like 60 plus percent, but that doesn't mean the air is 40% away from being total water. That would be ridiculous (but if the science interests you, relative humidity is to do with the ratio of the  pressure of water vapour to that of water....)  . So anyway, I will cut to the chase and a 'good' relative humidity for musical instruments made of wood is anywhere between about 40-55% relative humidity. At normal temperature. (And that last bit is equally important)

But why does this matter? Well - wood is a natural material and changes in temperature and relative humidity can affect how the wood behaves - mostly in terms of expansion and contraction. You see  a wooden ukulele absorbs and releases moisture and, being a technically built thing, that absorption and expansion can affect various parts of the build. In the simplest cases, it will throw tuning out, but in the worst cases it can BREAK an instrument. But here is the important thing. Most people bang on about the perils of low humidity - but high humidity can also be a problem!

Before we get into the details, first of all a couple of circumstances in which you probably don't need to read on with..

1. Laminate instruments - generally speaking, high or low humidity is not going to damage these instruments. Sure, I say 'generally' but by that I mean, 'so long as you don't leave them out in the Nevada sunshine or under the dripping leaves of an Amazonian rainforest'. Pretty much all other normal circumstance - you will be fine and don't need to buy a humidifier device. In fact, if you are prone to leaving your instrument in the Nevada sun or in a rainforest, you have bigger issues to deal with... Humidity mainly affects solid wood instruments.. (and no, all plastic instruments are not affected either...)

2. If you live in a temperate environment with a natural humidity in the 40-55 range. No need to worry so long as you keep them carefully (more on that later). Bear in mind that includes HUGE swathes of planet Earth and most of Europe. I've owned solid wood guitars and ukuleles for over 30 years and have NEVER bought a humidifying device. Guess what? Never had a problem. But then I have treated them carefully..

So, for many people these devices are just not required, yet shops and would be 'experts' will instil fear and worry into players which lead to one and one thing only - spending money you don't need to spend on more 'stuff'.

Yet, it must be said, many people DO live in areas of genuine low humidity. What can happen to a solid wood instrument if it is kept in such a place for a long time with no care?

Classic symptoms of a dry instrument may include:

- Strings getting closer to the fretboard (low action)
- A sunken top - the bridge area dipping
- Sharp fret ends
- Joints in the wood showing cracks
- Splits in the top of (or anywhere) on the body.

So for those people at risk, devices are available to put moisture back into an instrument. They are basically sponges, foams or gels that hold water and release it slowly over time, sitting in the case or in the sound hole (when in the case). Kind of like cigar aficionados use to keep their smokes in tip top condition. If you live in an area of low humidity I would naturally recommend them. But that is not really why I am writing this. You see, there are some other things you should bear in mind.

Firstly, applying humidification to an instrument that is normally kept in a temperate environment (and therefore doesn't need it)  can also damage it badly. If you have been applying humidification when you didn't need to you may note things like:

- Strings raising high in action
- Swollen top and back of the instrument
- Warped necks
- Bad neck angles
- Lifting bridges, joints etc

In fact - the same sort of damage as for a dry environment, but without the cracking - but damage all the same, and damage that can be just as irreparable. And it is much harder to revive an instrument that has taken on too much moisture!

But there is another factor that comes in to play - and that is temperature or rapid changes in temperature. No matter where you live you should treat your ukulele carefully and follow some rules. Rapid changes in temperature can kill an instrument, regardless of humidity. The rules seem obvious, but they are worthy of repeating:

- Keep a ukulele in a case whenever you can
- Do not store them in direct sunlight or next to a central heating source
- Do not store them in hot cars
- Do not store them in cold environments

If you do any of those, no matter what steps you have taken to protect against humidity issues, you are likely to destroy or at least damage an instrument if you then move it to an extreme the other way. The classic error is leaving a uke in the boot of a cold car then carrying it into a warm house or venue. CRACK!

But I digress... This was about people shilling the need for humidifiers that are not needed and people ignoring the damage that can be caused with over humidification. So to sum up...

- If you think you have a humidity problem - buy a humidity reader and test it before doing anything else. They are cheap to buy. Don't assume you have a problem just because 'Bob the ukulele expert' tells you that you do. Don't humidify an instrument for the sake of it!
- If you check your relative humidity over a period and it sits in the range of  40-55 (ish) you are fine so long as your storage choice is sensible
- Don't keep the uke next to a heat source
- Don't keep the uke in extreme cold
- If you DO live in an area of low humidity - get a humidifier device. But DONT be tempted to if you don't.


  1. from what i understand what really does a wood instrument in is fast changes in temperature and humidity. Leaving in a case will definitely help with sudden swings. Those of us who live in arid and desert climates, especially higher elevations are the ones who need to watch out. I would think that your local guitar/ukulele repair shop might be able to tell you a bit about how local conditions are. Just make sure they aren't trying to sell you something. Around here (colorado) I've seen more than a few with splits behind the bridge at places that do repairs.

  2. Best thing to do is keep it out of sun and away from extremes and in a case. Then buy a humidity gauge for the house and measure it over a few days. If it reads in the 40-60 range or so - do nothing. Humidifying at that range is not needed.

    Yes sudden swings can be fatal, but equally long term storage at low humidity can damage them too.

  3. Hi!
    I'm from Sweden. I thinking about buying a second hand Ko'olau ukulele from Thailand. The humidity in Thailand is much more than in Sweden, especially during winter time. Will that cause any problems for the instrument going from a high humidity region to a low humidity region?
    Merry christmas and thanks,

  4. @linh - at the end of the day - instruments that are prone to humidity damage (both guitars and ukes) do travel around the world all the time. My advice is it should be fine IF you take the following into account

    1. on arrival - leave in open box for 24 hours to acclimatise to your environment
    2. Keep in case when not played
    3. Keep away from heaters, sunlight, air conditioning - anything that generates an extreme either way.

    I live in a temperate area, but have had ukes from Hawaii, Nicaragua, Thailand, all over really - never had a problem if you treat them carefully

  5. The humidity gets pretty low in the winter here in Michigan. Still, I'd never had a problem before this year, my zebrawood uke cracked! It was repairable, but I started humidifying my nicer ukes after that. Probably just during the worst of Michigan's cold weather. The repair fella theorized the wood they used wasn't cured completely.

  6. Damn it, Baz! Will you never leave off being reasonable and correct? How will charlatans ever peddlle their useless crap with you around? Spot on. Don't spend money or take unnecessary (potentially harmful) measures to "solve" non-existent problems.

  7. ha ha! You know what though Lan - I swear some people only read the first line of some of my posts before they get offended and call me out as being wrong. Had someone today write me a diatribe pointing out exactly what this post says...


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